Trifluoroacetic Acid Mediated One-Pot Synthesis of Furo-Fused Quinoxalines/Pyrazines
作者:Kapil Mohan Saini、Sonu Kumar、Monika Patel、Rakesh K. Saunthwal、Akhilesh K. Verma
DOI:10.1002/ejoc.201700541
日期:2017.7.7
A trifluoroacetic acid promoted step-economical one-pot approach to the synthesis of furo-fused quinoxalines/pyrazines by the reaction of 2,3-dichloroquinoxalines/pyrazines with alkynes is described. The reaction involves a selective in-situ Sonogashira coupling step and a hydroxylation followed by a metal-free 5-endo-dig cyclization. Preliminary experiments show that trifluoroacetic acid acts as a
描述了通过2,3-二氯喹喔啉/吡嗪与炔烃反应合成呋喃稠合的喹喔啉/吡嗪的三氟乙酸促进的一步经济型一锅法。该反应包括选择性的原位Sonogashira偶联步骤和羟基化,然后是无金属的5 -endo-dig环化。初步实验表明,三氟乙酸是氧合步骤中的氧气来源,同位素标记研究支持了这种机制,即机理涉及酸性介质对炔烃的活化作用。可以耐受各种取代基,这对结构和生物学研究应具有重要意义。